


Simple Biology

by ectoBisexual



Category: Tokyo Ghoul
Genre: Awkwardness, Dirty Talk, Fingerfucking, Inappropriate Kagune Usage, M/M, Mating Cycles/In Heat, Poor Touka
Language: English
Status: Completed
Published: 2016-01-07
Updated: 2016-01-07
Packaged: 2018-05-07 01:07:00
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,056
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5437787
Author URL: https://archiveofourown.org/users/ectoBisexual/pseuds/ectoBisexual
Summary: <blockquote class="userstuff">
              <p>Kaneki has a problem.</p>
            </blockquote>





	Simple Biology

Kaneki has a problem.

He can handle a lot of things. Since becoming a ghoul, his capacity for Handling Things has become a lot greater, and his tolerance for weird has gone roughly from about a zero to a billion.

The people eating, he can handle. If it means his stomach isn’t going to gnaw and complain and he can just hide his face away in a coffee cup and pretend like he isn’t having a panic attack every time he thinks about the amount of people who want him dead—and the amount of people he sometimes wants dead—it’s endurable. The long stretches of hunger, the overshadowing mix of morality and starvation, often win out.

He can deal with the weird, territorial culture of ghouls, too, and has slowly been figuring it out himself. Sometimes he wonders whether they’re more animal than human, the way they operate off of instinct, smell, taste. He’s had to dodge Tsukiyama more times than he cares to count, and more than once now he’s accidentally wandered into another ghoul’s territory only to have to witness them start up some blatant show of dominance to intimidate him out of here, even as he’s been slinking away and apologising. Like wolves, or monsters, they operate on a system he doesn’t quite fully grasp yet. But it’s endurable. He can handle it.

This, he can’t handle.

“Kaneki, are you awake yet?”

It started as what felt like a mild fever as he was falling asleep. He excused himself early from the festivities downstairs when he started to feel a little lightheaded, blaming it on poor eating habits and a lack of exercise. He’d been so hungry lately, and anyway, it wasn’t like having ghoul blood in him granted him immunity from sickness forever. He was still part human after all, and it was flu season. Right?

Presently he attempts to stretch, only ending up curled in on himself in a defensive ball in bed. His head is pounding. Everything is swelteringly hot, a bone-deep need for something primal and instinctive driving him to stay still.

“Kaneki.” There’s another knock on the door, Touka’s voice like sharp instruments to his ears. It doesn’t hurt, exactly; it’s more like everything has gone hypersensitive, and his ear dums are vibrating at the sound.

She knocks again, and Kaneki thinks he’s going to go crazy.

“Just—just a second!” he calls, panting with the exertion. God, what’s wrong with him? “I’m coming.”

“You don’t sound well,” she calls. Before he knows what’s happening, she’s opening the door, furrowed brow and quizzically dark eyes peering in. At the sight of him, her brows shoot up to her hairline. “You don’t look well, either.”

“Gee, thanks.”

“I’m serious. It’s almost like you—hey, Yoshimura. Come here a moment.”

Kaneki closes his eyes and attempts to drown himself with his bed sheets. The old man’s head pops through his doorway moments later, wearing much the same expression as Touka.

“It’s probably just… the flu,” he wheezes, the light headedness returning. They’re looking at him like he’s grown an extra pair of limbs. “I might—really, I might just stay in bed today. You don’t need to worry about me.”

“Oh, dear,” says Yoshimura.

Touka turns to look at him like Kaneki isn’t even there. “Am I right? You don’t think he could be—”

“Is Uta still downstairs?”

“He’s waiting to go. We’re running late, so—”

“I’ll go fetch him,” Yoshimura says, cutting off Touka in the authoritarian tone he rarely uses without good reasoning. His tone makes Kaneki jump. “He’ll know a little more about this topic than you or I.”

Kaneki shuts his eyes and waits for the sound of Yoshimura’s retreating footsteps, the pound of them lasting for an eternity. When he opens them again he crashes gazes with Touka, who’s still staring like he just tried to kill her. When she doesn’t look away, he squirms, feeling absurdly exposed.

“Don’t you think this is a little bit of an overreaction to the flu?”

She stares at him a while longer before looking away again. “…Just wait for Uta, okay?”

If Kaneki’s not mistaken, she’s grinning.

Footsteps thunder up the stairs again. Kaneki feels each one of them as if it were pounding in his skull, his heartbeat hot and heavy barely a layer beneath his skin. He closes his eyes again, trying to quell the dizziness.

“Oh,” says Uta, from the doorway.

“Is it…?”

“Yes.”

“You’re sure? Just from looking at him?”

“Pretty sure. Unless you want to go check—”

There’s the sound of skin slapping skin. Kaneki opens his eyes, momentarily catches Touka going back in for another slap on a bored looking Uta’s face, before the room pulses and his eyes shut again. The three in the doorway go quiet, presumably watching him again.

“How is this possible?” Touka whispers.

“Rize was a female ghoul. It’s rare, but not unheard of. Spring just started, y’know?”

“Oh my God. What should we do?”

“Well, we can’t leave him like this. Who knows what he’ll do in this condition.”

Condition? Kaneki forces his eyes open again, briefly meeting Uta’s gaze. The other looks away momentarily, before meeting Kaneki’s eyes again… and winking. What the hell?

“What do you mean?” Touka questions, raising an eyebrow and shooting Kaneki another side glance. He feels like an animal in a zoo, no idea what he’s even being stared at for. He squirms again—and something white hot shoots through his system, shaking his whole frame.

The noise he makes gets the attention of the group for about a second, before Touka whips her head away again, face red. Kaneki stares after her. Fair enough it doesn’t feel exactly like a flu—there’s none of the nausea, or the sneezing or coughing, and his body feels too loose and lithe for its own good, but—

_Holylivingshithe’shard._

Kaneki shifts his hips, subtly trying to hide it under the bedcovers. So is that why Touka’s so embarrassed? Because he woke up with morning wood? He tries to will it away, thinking of broccoli—gore—Tsukiyama—but it all feels to no avail, his body just thrumming hotter. Something is seriously, dangerously wrong here. This isn’t normal sickness.

His whole body feels like it’s melting.

“I’ll stay here with him,” Uta offers, side-eyeing Kaneki in his bed again.

“Are you sure that’s a good idea?” Touka challenges. She still won’t look at him. “We could lock the door. It’s not like it’s—male hormones, so none of the aggression will be there. Won’t he be fine on his own?”

“Hm. I guess we could leave him here.” The way Uta is staring at him is making Kaneki feel exposed, the throbbing in his chest and temples leeching down and bleeding everywhere else. Uta’s stare is hot, pinning him to the bed. “I sure could use the entertainment.”

“He’s right, Touka. We just don’t know how he’ll react. There are customers downstairs, and I can’t be checking up on him all day.”

“…Yeah. Yeah, okay.”

Kaneki’s eyes flutter shut, listening to the warping sounds of Touka in the doorway. He can smell her, he realises; he can smell all three of them, coffee and blood and deodorant and—something else, something primal, distinct. Uta.

He can smell Uta.

The voices disappear into the hall, pieces and fragments moving back to him. He catches the gist of it. He’s too sick to go with the group, and Uta’s going to stay behind to watch him.

“—make sure he doesn’t leave the room, obviously—”

“—shouldn’t last much longer—”

“—well yeah, Touka. Do you remember your first heat?”

 _Heat_. Kaneki’s eyes shoot open.

What the fuck?

The three of his companions are standing in the hall now, just out of his site, but he can smell them—and he can certainly hear them. Heat? There’s no way. Kaneki’s just started to catch up on ghoul culture, norms, biology. He knows—knew—that female ghouls go through something akin to a mating ritual, once every few menstruation cycles... or something. He knows it means that Touka will take a few days off work, or that she’ll smell different for the few days leading up and the few days after. He knows this. But he also knows that this is meant to apply to female ghouls, and female ghouls only. What did Uta say about Rize? There’s no way—

Footsteps alert him to the presence of the group again. This time it’s two pairs retreating. Touka and Yoshimura leaving. Kaneki holds his breath, counts his heartbeat. One. Two. Three. Four. Uta enters the doorway of the room, shutting it neatly behind him.

“What’s going on?” Kaneki asks. The strain of his own voice surprises him; like his throat has been tightened, or he’s swallowed something and gotten it lodged in his throat. Uta chuckles under his breath like he finds this funny, and then—abruptly, no warning whatsoever—sits on the edge of Kaneki’s bed.

The smell hits him in the face. It’s overwhelming, coming from Uta’s pores as if in waves, and it makes Kaneki dizzy on his inhale. Why does he smell like that? God, he wants to—he wants—

“Whoa, easy there,” Uta says, blinking at Kaneki like a cat. Dazedly, Kaneki looks down at the hand on his chest, gently pressing him back into the bed. When did he start to get up? He looks around the room, trying to make sense of this situation.

“How are you feeling?”

“What’s going on?” Kaneki asks again, blurting the words out. Uta watches him carefully. After what feels like an eternity, the man shifts, the smell hitting Kaneki in the face again.

“You’re in heat. It’s something that happens ordinarily to female ghouls, but since the ghoul part of you came from Rize…” He trails off. Kaneki tries to glare at him, but just ends up closing his eyes again as a shudder move through him. It can’t be true. There’s no way. But…

“You must be feeling really hot,” Uta muses, humming under his breath. Kaneki curls up into himself. The chuckle that escapes Uta’s mouth sends another shudder through Kaneki’s body, and this time forces a whimper from his mouth. God, he can’t escape it. It feels like it’s growing, spreading hot throughout his bloodstream and causing his head to pound. He’s still painfully hard, the blood dropping rapidly from his head, and there’s something slick between his legs, almost as if it’s pooling there. Confused, Kaneki tries to sit up again, pawing at the sheets to get them out of the way.

“Careful,” Uta says. His voice comes measured and cool, like soothing ice to the heat coursing through Kaneki. Rather than lying back again, he rests his head on one of his propped knees, shivering. He can feel Uta watching him, the pierce of his gaze like knives.

“…You can touch yourself, you know.”

“What?” Kaneki whips his head up. The motion makes him dizzy again, and the force of Uta’s words sends another jolt straight through his stomach.

“You want to, right?” Uta’s expression is unreadable. Kaneki would think he looked bored, if it weren’t for the intense focus of his gaze. The blackness of his eyes has always been kind of unnerving, just another Ghoul Thing to get used to for Kaneki, but right now it’s beyond intense. Almost—

“Hot?” Uta offers. Kaneki blinks.

“I’m sorry?”

Uta smiles. “Are you still feeling hot? How’s the fever, Ka-ne-ki?”

Kaneki shudders as the man’s hand touches his forehead, the cool skin soothing him immediately. Without meaning to he presses closer, desperate for more contact.

“I mean what I said,” Uta murmurs, moving the back of his hand down to Kaneki’s flushed cheek. “I really don’t mind if you wanna touch yourself. Might be fun.”

“We’re both guys,” Kaneki gasps out, feeling the constricting urge to pant rising in his chest again. Uta laughs like it’s a weak excuse, which it is.

“Mhm. I’m sure you’re absolutely horrified by the idea of another man being close to you in any sort of sexual context. I’ll just be sitting here. You can do what you like.”

Kaneki considers it. The throbbing between his legs is getting painful now. It doesn’t seem like there’s any chance of Uta leaving; he said so himself, that Kaneki needed to be watched. God. How long can he keep this up, without needing to get himself off?

Hesitantly, fingers shaking, he starts to reach down. "Yeah," Uta says, grinning lazily. "Go ahead."

Kaneki draws his hand back. He can't-- he  _can't,_ it's so embarrassing that he's going to die. The adventurous streak in him isn't even half as big enough for him to ignore that fact. Whining under his breath, he tries to hide behind his own hands, only to find another pair tugging him gently away from his hiding place. Uta's eyes are staring into his, unsettling. Without once breaking eye contact, he places his hand on Kaneki's lower stomach.

Kaneki's hips jump. The noise that leaves his mouth is far from dignified, somewhere between an "ah" and an "oh". Embarrassed, he tries to hide his face in Uta's shoulder, shaking.

"Hm. Cute. So you don't want to touch yourself, I take it. That's fine. But you'll be a lot more uncomfortable if you don't get any relief."

The thought jumps into his mind so fast it makes the room spin.  _You should touch me._ He wants to take it back immediately, but he'd be lying to himself; he  _wants_ Uta to touch him, so badly that his body goes warm at the thought. 

"I wonder," continues Uta, in that calm, unfeeling voice that tells Kaneki nothing he needs to know. "Whether... hm. Kaneki, could it be that you want  _me_ to touch you instead?"

The heat shoots through his body. It's like a series of manifested bullets, traveling from Uta's mouth to his body. He understands why they call it  _heat;_ everything is swelteringly hot, clouding his brain and sight and better judgement. Uta is waiting for his answer. Slowly, the barest of movements, so subtle that it could almost be missed, Kaneki nods. 

The first touch of Uta's hand is gentle. He lowers and rests the flat palm of his hand against where Kaneki is tenting his pants, drawing a sharp gasp from the other man. Lazily he begins to move his fingers around the length of Kaneki, petting him through the fabric, grinning every time the shorter's breath warbles. "This is good," he says placidly. "This is nice. I like this."

"Ah," Kaneki says, the noise involuntary. Uta's hand is beneath his pajama shorts now, fingers curling around his dick and starting up a decent rhythm. Kaneki ducks his head and lets out a pitiful mewl. The heat is unbearable now, the urge to-- to move his hips, to  _do something._ Every time his eyes flutter open he finds Uta watching him. It's unnerving.

Before long it gets painful. Something must be wrong; Kaneki feels so  _close,_ too close, but somehow unbelievably far from climax too. His hips roll uselessly towards Uta's hand. His wrist is still moving leisurely, in no rush.  _  
_

"Oh, dear," he says, when Kaneki's frustrated noises pick up in their intensity. "That's right, isn't it? This just isn't going to satisfy a heat. Sure, for a minute, maybe, but..."

" _What,_ " Kaneki gasps, dragging him down by the collar. " _Tell me what to do to make it stop._ Ha-- Uta, it's bad, it's-- I just want it to stop, or-- I don't know _what_ I want exactly, but--"

"You need to be fucked," Uta says curtly. Kaneki blinks at him. If he weren't so turned on and hazy, he would probably balk.

"W...what--"

"You're in heat, Kaneki. To satisfy that heat, you need to get fucked." He examines the room casually, as if his hand isn't currently down the other's pants. Kaneki lifts his hips impatiently when Uta stops moving for a moment and a grin flickers across his otherwise impervious expression.

"F..." Kaneki doesn't even want to say the word. He's  _humiliated_ now, cheeks burning-- the flush going all the way down his chest-- and wants to hide. He wants to get away from Uta, move closer to him. Uta is watching with an expectant twinkle in his eyes. He knows exactly what Kaneki's thinking, what he wants. He's waiting for him to say it.

"C-could you..."

"Could I?"

" _Fuck._ " Kaneki slams his head back down on the other's shoulder, hips moving restlessly. Uta thumbs over the head of his dick again, ever casual, humming under his breath and waiting for the tremors to leave Kaneki's voice. "Mm-- please, make it better."

"Make what better? Kaneki? You're going to have to be a little more specific."

" _Fuck me,_ please. God, just--"

He doesn't get the chance to finish his sentence. Uta's hands are pushing him back against the mattress, the other male looming over him suddenly as if he's been waiting the whole time for this.

Uta isn't rough, but he isn't gentle, either. He's confident, his movements powerful and authoritarian. Kaneki doesn't know whether to be more shocked or humiliated at himself for getting off on it, for actually  _liking_ the feeling of not being in control. Is it the heat, or is it him? He doesnt want to think about it--

" _Ah,"_ he rasps. Uta has tugged his pants down casually and is now eyeing him off like he's something to eat. Kaneki squirms under the ministrations, not sure whether he wants to get away or move closer again. Humiliation is blurring itself with desire like camoflague; he wants to be touched, he knows that much.

As if reading his thoughts, Uta's hand ghosts over Kaneki's erection again. Ignoring the way the other gasps, the hand continues its descent down, another hand coming to move and prop up Kaneki by his thighs. He realises where it's going a beat too late; Uta's fingers brush over his entrance, and Kaneki's body jumps. _  
_

"Th-that's," he says, but he doesn't finish the thought. What was he expecting? He asked to be fucked; he doesn't expect the feeling to be so wet, as if slick is pooling there. Another heat side effect? Whatever it is, it ceases to matter altogether when Uta breaches him. Just the tip of his finger, but it sets Kaneki's nerves on fire.

"Oh," he says, the noise coming out through a gasp in his parted lips. Uta chuckles. Taking his time, he wiggles his finger in deeper, stopping when he's at the first knuckle. Kaneki relaxes around it without having to be asked. He's done this much before-- alone in his room, embarrassed, at night-- and reminds himself how to keep his hips up, how to relax his muscles. 

"Okay?" Uta asks, looking for consent. The look on his face is casual, a total contrast to the feeling of another finger sliding in alongside the first one. He pushes them  both down to the last knuckle when Kaneki nods his head. Keeping eye contact, he crooks them.

It misses Kaneki's prostate by barely half of an inch, but he suspects Uta knows this. The moan that spills out of his mouth is breathy and shaky, desperation edging along the tenor of it; Uta continues to watch him, crooking his fingers again. This time it brushes Kaneki's prostate, but it's too soft to do much other than tease.

He works him up that way, relaxing him and edging him with three, then four fingers. By the end of it Kaneki is a shivering wreck, blindly pawing for Uta's shoulders to bring the other's body towards his. Uta says nothing until Kaneki starts to work off his belt, his voice coming out casual still.

"Oh, no, not like that. Heat works a little differently, you know? Well, you don't know."

Kaneki tries to glare at him. He doesn't imagine it works well, with the heavy lidded bedroom eyes and all. The next thing he knows Uta is moving back and he's cold everywhere the man was touching, whining for contact. 

It takes him a moment to catch on to why Uta is sitting up. Slowly, it dawns on him that the man's kagune is coming out.

"That's...  _definitely_ what that's for."

"Sure it is." Uta shrugs. "Like I said, heat works a little differently."

"You  _kill_ people with that thing. _I've_ killed people with  _mine._ "

"Yes, I do. I've also fucked with... well, you'll see."

Kaneki doesn't get the chance to protest. He's being pressed back against the mattress again, legs spread open. He wants to protest, but what's the use? He wants it so bad he's _dripping_ for it. Uta pauses at his entrance again anyway, looking up to meet his eyes.

"Okay?" he asks, tilting his head. Kaneki sucks in a breath. 

He nods.

The first breach doesn't sting like he expects it to, but it burns. Not in a painful way, but in a surprisingly _intense_ way, heat blossoms over the lower half of his body and slowly rises, a tingling feeling so strong that Kaneki has to clench his toes. "Mmn," he murmurs, throat contracting around sounds that want to come out of it. Uta pauses to let Kaneki's body accommodate, squirming gently, teasingly against his walls.

"Feeling okay?" he asks again.

"Yeah, just..." He cuts off with a warbled moan when Uta pushes forward, more of his length moving inside of Kaneki. It's a stretch-- burns for a second, before the warmth is back-- and without meaning to Kaneki pushes back against it, shuddering deeply. "Just...  _move,_ Uta."

Uta hums in amusement. "Sure. I can do that."

One more thrust has Kaneki feeling  _full,_ achingly so, the tremors moving from his hips and thighs and abdomen to spread over his full body like a flush. Without meaning to he lifts his hips twice, squirming restlessly on the other's kagune.

Uta laughs under his breath. "Yeah, there you go. You feeling good now?"

"Uta," Kaneki gasps out. His mouth opens and closes around a moan. Uta finally sets a rhythm, fucking in earnest.

"Kaneki," he hums back, like he's curious, trying it out. At the look on Kaneki's face he grins, picking up the pace. Kaneki shudders and groans and shuts his eyes.

Uta's apparently done playing around now, because the pace picks up significantly. Kaneki bounces back on the bed with it, lifting his hips and letting out a moan that sounds more like a sob. He's  _so_ close, everything hurts and aches so  _good_ and his mind has gone off somewhere without him. He fucks back onto Uta without meaning it, and the tip of his kagune, soft and pliable now to accommodate for Kaneki's body, pushes his prostate like a bruise.

The force of his own orgasm nearly blinds him. Kaneki's hips lock up and he feels tears finally spill, pleasure overwhelming his senses, heat reaching his head. When he comes to moments later his back is flat against the bed and he's panting. Uta is retracting his kagune, but where Kaneki expects to see him grinning wickedly, teasingly, the other simple looks placated.

Kaneki opens his mouth-- to ask him God knows what-- but Uta seems to know anyway,  _tsk_ ing under his breath. He moves to help lift Kaneki's hips back under the covers, smoothing it over his body and up to his chin. The sleepiness hits him with the force of a truck. The hotness is dying down now to a dull warmth, and Kaneki sinks into it, curling in on himself and the bed.

"Is it over?" he murmurs, feeling himself on the verge of sleep. Uta makes a noise of consideration under his breath.

"Probably not. Sleep, now. I'll be here when you wake up."

Kaneki wants to ask him about that, why he's staying. But sleep is overtaking him so fast. He think he could probably get used to this whole heat thing, if he had someone like Uta there to help him through it.

"My kagune will still be here when you wake up, too."

"Shut up."

He falls asleep with that thought on his mind. When he wakes up, Uta will be there waiting.


End file.
